SummaryWe describe a new method for synchronizing bacterial cells. Cells that have transiently expressed an inducible mutant 'sticky' flagellin are adhered to a volume of glass beads suspended in a chromatography column though which growth medium is pumped. Following repression of flagellin synthesis, newborn cells are eluted from the column in large quantities exceeding that of current baby machine techniques by approximately 10-fold. Eluted cultures of 'baby cells' are highly synchronous as determined by analysis of DNA replication, cell division and other events, over time after elution from the column. We also show that use of 'minutes after elution' as a time metric permits much greater temporal resolution among sequential chromosomal events than the commonly used metric of cell size (length). The former approach reveals the existence of transient intermediate stages that are missed by the latter approach. This finding has two important implications. First, at a practical level, the baby cell column is a particularly powerful method for temporal analysis. Second, at a conceptual level, replication-related events are more tightly linked to cell birth (i.e. cell division) than to absolute cell mass.

Many research groups have attained slow, persistent, continuous release of silver ions through careful experimental design using existing methods. Such methods effectively kill planktonic bacteria and therefore prevent surface adhesion of pathogens. However, the resultant modified coatings cannot provide long-term antibacterial efficacy due to sustained anti-microbial release. In this study, the anti-infection activity of AgNP immobilized biomaterials was evaluated, facilitated by argon plasma grafting technology and activated by bacterial colonization. The modified materials generated in this study showed excellent specificity and were active against both Gram-positive and Gram-negative biofilm forming bacteria, including methicillin-resistant Staphylococcus aureus, Staphylococcus epidermidis, and Escherichia coli. The anti-infection biomaterials developed in this study demonstrate several attractive advantages in comparison to traditional anti-bacterial surfaces loaded with antibiotics or other types of antibacterial agents and include (1) broad spectrum of activity against antibiotic resistant bacteria, (2) the unlikelihood of bacterial resistance, (3) specificity, (4) biocompatibility, and (5) stability.

Income is the standard indicator of low-end households’ living standards. With income as the measure, the comparative evidence suggests that economic growth has tended to be the principal driver of improved living standards, though government social programs have been the chief conduit through which growth trickles down. Material deprivation may be a better indicator. With deprivation as the measure, the available evidence suggests an even stronger and more direct impact of social policy.

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In this project for the organic chemistry laboratory, we bring together and expand upon two classic undergraduate organic chemistry experiments to create a flavor chemistry unit in which students design and develop a novel smelling product. The scents are derived from a synthetic angle, utilizing an expanded ester synthesis, and from a natural products angle by the isolation of fragrance molecules from natural materials using classic extraction techniques. Students are given an overview of flavor chemistry, and each group designs a novel product: a scented soap or candle. The project culminates in an oral presentation and a written report that is submitted in a journal style format for grading.

Discussion about weapons of mass destruction (WMD) has increased since so many saw the World Trade Towers collapse. The term evokes anxiety, political debate, and ethical concerns. But, what are WMD and how do the work? The topics involved with WMD touch many areas of chemistry, including general chemistry, organic chemistry, and biochemistry. A discussion of WMD can be brought into the classroom in many subjects. These subjects correlate with the curriculum and stimulate students to engage with chemistry content.

Since the mid‐1990s, formal scientific risk management has been codified at all levels of food safety governance in affluent states: firm‐level standards, national regulation, and international law. Developing countries' access to affluent importers and power in international standard‐setting fora now hinges on their scientific capacity. This article explores the consequences of these developments in India, which moved quickly from resistance to acquiescence, and then later to mobilization around narratives of scientific risk management's local benefits. The case suggests a two‐stage model of scientization among developing countries: (1) coercive and competitive mechanisms drive adoption of science‐based governance models, and (2) as local actors mobilize to meet foreign demands, they attach their own interests and agendas to science‐based reforms. The outcome is a set of rational myths about the benefits of scientization. The article draws on content analysis of organizational, policy, and news documents and a small set of interviews with highly placed pubic officials and industry representatives.